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Accurate list of Keywords / Datatypes?
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* Accurate list of Keywords / Datatypes?
@ 2016-05-08 01:53 Robins Tharakan <[email protected]>
  2016-05-08 02:08 ` Re: Accurate list of Keywords / Datatypes? Euler Taveira <[email protected]>
  0 siblings, 1 reply; 26466+ messages in thread

From: Robins Tharakan @ 2016-05-08 01:53 UTC (permalink / raw)
  To: pgsql-hackers

Hi,

While creating a Syntax Highlighting XML for Notepad++ (something like a
PLSQL one here http://goo.gl/UBbHdt ), I was looking for a list of Keywords
(& separately list of Datatypes) that Postgres uses in a given version (Say
DEVEL branch).

I did find the Reserved Keyword list (
http://www.postgresql.org/docs/devel/static/sql-keywords-appendix.html) but
it doesn't look like what I need, because:

1. The ones marked as 'Reserved' isn't all the words I am interested in
(since these are just 'Reserved')
2. The entire list seems like an overkill (since it has words such as K
and ROUTINE_CATALOG, which aren't really what I'd like highlighted when I
am working on an SQL file in NPP)

Should I be looking somewhere else? Parse keywords from Git Source file (if
so where)? Parse PG Documentation?

I tried ( https://goo.gl/OYeYuE ) parsing HTML Tags (such as VARNAME /
TOKEN / LITERAL / COMMAND) in PG Documentation but is there's a simpler
(more accurate) way for this?

Any pointers would be great!
-
​thanks
robins


^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* Re: Accurate list of Keywords / Datatypes?
  2016-05-08 01:53 Accurate list of Keywords / Datatypes? Robins Tharakan <[email protected]>
@ 2016-05-08 02:08 ` Euler Taveira <[email protected]>
  2016-05-11 01:22   ` Re: Accurate list of Keywords / Datatypes? David G. Johnston <[email protected]>
  2016-05-11 03:36   ` Re: Accurate list of Keywords / Datatypes? Robins Tharakan <[email protected]>
  0 siblings, 2 replies; 26466+ messages in thread

From: Euler Taveira @ 2016-05-08 02:08 UTC (permalink / raw)
  To: Robins Tharakan <[email protected]>; pgsql-hackers

On 07-05-2016 22:53, Robins Tharakan wrote:
> Should I be looking somewhere else? Parse keywords from Git Source file
> (if so where)? Parse PG Documentation?
> 
src/include/parser/kwlist.h


-- 
   Euler Taveira                   Timbira - http://www.timbira.com.br/
   PostgreSQL: Consultoria, Desenvolvimento, Suporte 24x7 e Treinamento


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^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* Re: Accurate list of Keywords / Datatypes?
  2016-05-08 01:53 Accurate list of Keywords / Datatypes? Robins Tharakan <[email protected]>
  2016-05-08 02:08 ` Re: Accurate list of Keywords / Datatypes? Euler Taveira <[email protected]>
@ 2016-05-11 01:22   ` David G. Johnston <[email protected]>
  2016-05-11 02:50     ` Re: Accurate list of Keywords / Datatypes? Michael Paquier <[email protected]>
  2016-05-11 02:51     ` Re: Accurate list of Keywords / Datatypes? Euler Taveira <[email protected]>
  1 sibling, 2 replies; 26466+ messages in thread

From: David G. Johnston @ 2016-05-11 01:22 UTC (permalink / raw)
  To: Euler Taveira <[email protected]>; +Cc: Robins Tharakan <[email protected]>; pgsql-hackers

On Saturday, May 7, 2016, Euler Taveira <[email protected]> wrote:

> On 07-05-2016 22:53, Robins Tharakan wrote:
> > Should I be looking somewhere else? Parse keywords from Git Source file
> > (if so where)? Parse PG Documentation?
> >
> src/include/parser/kwlist.h


>
 http://www.postgresql.org/docs/9.5/interactive/functions-info.html

SELECT * FROM pg_get_keywords();

I don't know how the docs, this function, and the source code relate to
each other.

David J.


^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* Re: Accurate list of Keywords / Datatypes?
  2016-05-08 01:53 Accurate list of Keywords / Datatypes? Robins Tharakan <[email protected]>
  2016-05-08 02:08 ` Re: Accurate list of Keywords / Datatypes? Euler Taveira <[email protected]>
  2016-05-11 01:22   ` Re: Accurate list of Keywords / Datatypes? David G. Johnston <[email protected]>
@ 2016-05-11 02:50     ` Michael Paquier <[email protected]>
  1 sibling, 0 replies; 26466+ messages in thread

From: Michael Paquier @ 2016-05-11 02:50 UTC (permalink / raw)
  To: David G. Johnston <[email protected]>; +Cc: Euler Taveira <[email protected]>; Robins Tharakan <[email protected]>; pgsql-hackers

On Wed, May 11, 2016 at 10:22 AM, David G. Johnston
<[email protected]> wrote:
> On Saturday, May 7, 2016, Euler Taveira <[email protected]> wrote:
>>
>> On 07-05-2016 22:53, Robins Tharakan wrote:
>> > Should I be looking somewhere else? Parse keywords from Git Source file
>> > (if so where)? Parse PG Documentation?
>> >
>> src/include/parser/kwlist.h
>>
>>
>
>  http://www.postgresql.org/docs/9.5/interactive/functions-info.html
>
> SELECT * FROM pg_get_keywords();
>
> I don't know how the docs, this function, and the source code relate to each
> other.

ScanKeywords is fed directly from kwlist.h, have for example a look at
the top of src/common/keywords.c. Then NumScanKeywords is calculated
from the list generated. pg_get_keywords is at the end making use of
those structures generated.
-- 
Michael


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^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* Re: Accurate list of Keywords / Datatypes?
  2016-05-08 01:53 Accurate list of Keywords / Datatypes? Robins Tharakan <[email protected]>
  2016-05-08 02:08 ` Re: Accurate list of Keywords / Datatypes? Euler Taveira <[email protected]>
  2016-05-11 01:22   ` Re: Accurate list of Keywords / Datatypes? David G. Johnston <[email protected]>
@ 2016-05-11 02:51     ` Euler Taveira <[email protected]>
  1 sibling, 0 replies; 26466+ messages in thread

From: Euler Taveira @ 2016-05-11 02:51 UTC (permalink / raw)
  To: David G. Johnston <[email protected]>; +Cc: Robins Tharakan <[email protected]>; pgsql-hackers

On 10-05-2016 22:22, David G. Johnston wrote:
> I don't know how the docs, this function, and the source code relate to
> each other.
> 
Function is built around ScanKeywords structure which in turn is built
using parser/kwlist.h.


-- 
   Euler Taveira                   Timbira - http://www.timbira.com.br/
   PostgreSQL: Consultoria, Desenvolvimento, Suporte 24x7 e Treinamento


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* Re: Accurate list of Keywords / Datatypes?
  2016-05-08 01:53 Accurate list of Keywords / Datatypes? Robins Tharakan <[email protected]>
  2016-05-08 02:08 ` Re: Accurate list of Keywords / Datatypes? Euler Taveira <[email protected]>
@ 2016-05-11 03:36   ` Robins Tharakan <[email protected]>
  1 sibling, 0 replies; 26466+ messages in thread

From: Robins Tharakan @ 2016-05-11 03:36 UTC (permalink / raw)
  To: Euler Taveira <[email protected]>; +Cc: pgsql-hackers

On 8 May 2016 at 07:38, Euler Taveira <[email protected]> wrote:

> src/include/parser/kwlist.h


​Thanks Everyone.

Kwlist.h got me going as to where to look, but I had to improvise (quite) a
bit. Any and all advice about any other authoritative lists (like kwlist.h)
would be a big help, since currently much is kludgy.

Created a GitHub Repo in case someone's interested (
https://github.com/robins/npp-lang-plpgsql).

​For PLPGSQL, (src/pl/plpgsql/src/pl_scanner.c)​

For DataTypes, (src/interfaces/ecpg/preproc/c_keywords.c
; src/backend/bootstrap/bootstrap.c) as well as parse all HTML pages under
http://www.postgresql.org/docs/devel/static/datatype.html.

For Config Parameters (recovery.sample.conf ; postgresql.sample.conf) as
well as parse all HTML pages under
http://www.postgresql.org/docs/devel/static/runtime-config.html ;
http://www.postgresql.org/docs/devel/static/libpq-connect.html

For Extensions (Parse HTML:
http://www.postgresql.org/docs/devel/static/contrib.html)

-
robins


^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


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Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


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Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


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Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


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Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


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Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


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Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


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Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


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Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


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Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


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Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


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Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


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Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


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Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


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Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


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Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


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Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


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Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


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Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v1 5/7] Row pattern recognition patch (docs).
@ 2023-06-25 11:48 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 51 ++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 18 ++++++++--
 3 files changed, 136 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..23ee285b40 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,57 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..c0fc16d773 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses.
+
+<synopsis>
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Sun_Jun_25_21_05_09_2023_126)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v1-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v2 5/7] Row pattern recognition patch (docs).
@ 2023-06-26 08:05 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-26 08:05 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 52 +++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 29 +++++++++++++--
 3 files changed, 148 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..e9bbd5bc7c 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,58 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ AFTER MATCH SKIP PAST LAST ROW
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..16478a3950 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,31 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses. <literal>AFTER MATCH SKIP PAST LAST
+    ROW</literal> or <literal>AFTER MATCH SKIP TO NEXT ROW</literal> controls
+    how to proceed to next row position after a match
+    found. With <literal>AFTER MATCH SKIP PAST LAST ROW</literal> (the
+    default) next row position is next to the last row of previous match. On
+    the other hand, with <literal>AFTER MATCH SKIP TO NEXT ROW</literal> next
+    row position is always next to the last row of previous
+    match. <literal>DEFINE</literal> defines definition variables along with a
+    boolean expression. <literal>PATTERN</literal> defines a sequence of rows
+    that satisfies certain conditions using variables defined
+    in <literal>DEFINE</literal> clause.
+
+<synopsis>
+[ AFTER MATCH SKIP PAST LAST ROW | AFTER MATCH SKIP TO NEXT ROW ]
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Mon_Jun_26_17_45_07_2023_724)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v2-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v2 5/7] Row pattern recognition patch (docs).
@ 2023-06-26 08:05 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-26 08:05 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 52 +++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 29 +++++++++++++--
 3 files changed, 148 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..e9bbd5bc7c 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,58 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ AFTER MATCH SKIP PAST LAST ROW
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..16478a3950 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,31 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses. <literal>AFTER MATCH SKIP PAST LAST
+    ROW</literal> or <literal>AFTER MATCH SKIP TO NEXT ROW</literal> controls
+    how to proceed to next row position after a match
+    found. With <literal>AFTER MATCH SKIP PAST LAST ROW</literal> (the
+    default) next row position is next to the last row of previous match. On
+    the other hand, with <literal>AFTER MATCH SKIP TO NEXT ROW</literal> next
+    row position is always next to the last row of previous
+    match. <literal>DEFINE</literal> defines definition variables along with a
+    boolean expression. <literal>PATTERN</literal> defines a sequence of rows
+    that satisfies certain conditions using variables defined
+    in <literal>DEFINE</literal> clause.
+
+<synopsis>
+[ AFTER MATCH SKIP PAST LAST ROW | AFTER MATCH SKIP TO NEXT ROW ]
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Mon_Jun_26_17_45_07_2023_724)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v2-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v2 5/7] Row pattern recognition patch (docs).
@ 2023-06-26 08:05 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-26 08:05 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 52 +++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 29 +++++++++++++--
 3 files changed, 148 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..e9bbd5bc7c 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,58 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ AFTER MATCH SKIP PAST LAST ROW
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..16478a3950 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,31 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses. <literal>AFTER MATCH SKIP PAST LAST
+    ROW</literal> or <literal>AFTER MATCH SKIP TO NEXT ROW</literal> controls
+    how to proceed to next row position after a match
+    found. With <literal>AFTER MATCH SKIP PAST LAST ROW</literal> (the
+    default) next row position is next to the last row of previous match. On
+    the other hand, with <literal>AFTER MATCH SKIP TO NEXT ROW</literal> next
+    row position is always next to the last row of previous
+    match. <literal>DEFINE</literal> defines definition variables along with a
+    boolean expression. <literal>PATTERN</literal> defines a sequence of rows
+    that satisfies certain conditions using variables defined
+    in <literal>DEFINE</literal> clause.
+
+<synopsis>
+[ AFTER MATCH SKIP PAST LAST ROW | AFTER MATCH SKIP TO NEXT ROW ]
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Mon_Jun_26_17_45_07_2023_724)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v2-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v2 5/7] Row pattern recognition patch (docs).
@ 2023-06-26 08:05 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-26 08:05 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 52 +++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 29 +++++++++++++--
 3 files changed, 148 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..e9bbd5bc7c 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,58 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ AFTER MATCH SKIP PAST LAST ROW
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..16478a3950 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,31 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses. <literal>AFTER MATCH SKIP PAST LAST
+    ROW</literal> or <literal>AFTER MATCH SKIP TO NEXT ROW</literal> controls
+    how to proceed to next row position after a match
+    found. With <literal>AFTER MATCH SKIP PAST LAST ROW</literal> (the
+    default) next row position is next to the last row of previous match. On
+    the other hand, with <literal>AFTER MATCH SKIP TO NEXT ROW</literal> next
+    row position is always next to the last row of previous
+    match. <literal>DEFINE</literal> defines definition variables along with a
+    boolean expression. <literal>PATTERN</literal> defines a sequence of rows
+    that satisfies certain conditions using variables defined
+    in <literal>DEFINE</literal> clause.
+
+<synopsis>
+[ AFTER MATCH SKIP PAST LAST ROW | AFTER MATCH SKIP TO NEXT ROW ]
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Mon_Jun_26_17_45_07_2023_724)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v2-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v2 5/7] Row pattern recognition patch (docs).
@ 2023-06-26 08:05 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-26 08:05 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 52 +++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 29 +++++++++++++--
 3 files changed, 148 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..e9bbd5bc7c 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,58 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ AFTER MATCH SKIP PAST LAST ROW
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..16478a3950 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,31 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses. <literal>AFTER MATCH SKIP PAST LAST
+    ROW</literal> or <literal>AFTER MATCH SKIP TO NEXT ROW</literal> controls
+    how to proceed to next row position after a match
+    found. With <literal>AFTER MATCH SKIP PAST LAST ROW</literal> (the
+    default) next row position is next to the last row of previous match. On
+    the other hand, with <literal>AFTER MATCH SKIP TO NEXT ROW</literal> next
+    row position is always next to the last row of previous
+    match. <literal>DEFINE</literal> defines definition variables along with a
+    boolean expression. <literal>PATTERN</literal> defines a sequence of rows
+    that satisfies certain conditions using variables defined
+    in <literal>DEFINE</literal> clause.
+
+<synopsis>
+[ AFTER MATCH SKIP PAST LAST ROW | AFTER MATCH SKIP TO NEXT ROW ]
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Mon_Jun_26_17_45_07_2023_724)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v2-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v2 5/7] Row pattern recognition patch (docs).
@ 2023-06-26 08:05 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-26 08:05 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 52 +++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 29 +++++++++++++--
 3 files changed, 148 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..e9bbd5bc7c 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,58 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ AFTER MATCH SKIP PAST LAST ROW
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..16478a3950 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,31 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses. <literal>AFTER MATCH SKIP PAST LAST
+    ROW</literal> or <literal>AFTER MATCH SKIP TO NEXT ROW</literal> controls
+    how to proceed to next row position after a match
+    found. With <literal>AFTER MATCH SKIP PAST LAST ROW</literal> (the
+    default) next row position is next to the last row of previous match. On
+    the other hand, with <literal>AFTER MATCH SKIP TO NEXT ROW</literal> next
+    row position is always next to the last row of previous
+    match. <literal>DEFINE</literal> defines definition variables along with a
+    boolean expression. <literal>PATTERN</literal> defines a sequence of rows
+    that satisfies certain conditions using variables defined
+    in <literal>DEFINE</literal> clause.
+
+<synopsis>
+[ AFTER MATCH SKIP PAST LAST ROW | AFTER MATCH SKIP TO NEXT ROW ]
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Mon_Jun_26_17_45_07_2023_724)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v2-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v2 5/7] Row pattern recognition patch (docs).
@ 2023-06-26 08:05 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-26 08:05 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 52 +++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 29 +++++++++++++--
 3 files changed, 148 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..e9bbd5bc7c 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,58 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ AFTER MATCH SKIP PAST LAST ROW
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..16478a3950 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,31 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses. <literal>AFTER MATCH SKIP PAST LAST
+    ROW</literal> or <literal>AFTER MATCH SKIP TO NEXT ROW</literal> controls
+    how to proceed to next row position after a match
+    found. With <literal>AFTER MATCH SKIP PAST LAST ROW</literal> (the
+    default) next row position is next to the last row of previous match. On
+    the other hand, with <literal>AFTER MATCH SKIP TO NEXT ROW</literal> next
+    row position is always next to the last row of previous
+    match. <literal>DEFINE</literal> defines definition variables along with a
+    boolean expression. <literal>PATTERN</literal> defines a sequence of rows
+    that satisfies certain conditions using variables defined
+    in <literal>DEFINE</literal> clause.
+
+<synopsis>
+[ AFTER MATCH SKIP PAST LAST ROW | AFTER MATCH SKIP TO NEXT ROW ]
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Mon_Jun_26_17_45_07_2023_724)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v2-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v2 5/7] Row pattern recognition patch (docs).
@ 2023-06-26 08:05 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-26 08:05 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 52 +++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 29 +++++++++++++--
 3 files changed, 148 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..e9bbd5bc7c 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,58 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ AFTER MATCH SKIP PAST LAST ROW
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..16478a3950 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,31 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses. <literal>AFTER MATCH SKIP PAST LAST
+    ROW</literal> or <literal>AFTER MATCH SKIP TO NEXT ROW</literal> controls
+    how to proceed to next row position after a match
+    found. With <literal>AFTER MATCH SKIP PAST LAST ROW</literal> (the
+    default) next row position is next to the last row of previous match. On
+    the other hand, with <literal>AFTER MATCH SKIP TO NEXT ROW</literal> next
+    row position is always next to the last row of previous
+    match. <literal>DEFINE</literal> defines definition variables along with a
+    boolean expression. <literal>PATTERN</literal> defines a sequence of rows
+    that satisfies certain conditions using variables defined
+    in <literal>DEFINE</literal> clause.
+
+<synopsis>
+[ AFTER MATCH SKIP PAST LAST ROW | AFTER MATCH SKIP TO NEXT ROW ]
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Mon_Jun_26_17_45_07_2023_724)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v2-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v2 5/7] Row pattern recognition patch (docs).
@ 2023-06-26 08:05 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-26 08:05 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 52 +++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 29 +++++++++++++--
 3 files changed, 148 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..e9bbd5bc7c 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,58 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ AFTER MATCH SKIP PAST LAST ROW
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..16478a3950 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,31 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses. <literal>AFTER MATCH SKIP PAST LAST
+    ROW</literal> or <literal>AFTER MATCH SKIP TO NEXT ROW</literal> controls
+    how to proceed to next row position after a match
+    found. With <literal>AFTER MATCH SKIP PAST LAST ROW</literal> (the
+    default) next row position is next to the last row of previous match. On
+    the other hand, with <literal>AFTER MATCH SKIP TO NEXT ROW</literal> next
+    row position is always next to the last row of previous
+    match. <literal>DEFINE</literal> defines definition variables along with a
+    boolean expression. <literal>PATTERN</literal> defines a sequence of rows
+    that satisfies certain conditions using variables defined
+    in <literal>DEFINE</literal> clause.
+
+<synopsis>
+[ AFTER MATCH SKIP PAST LAST ROW | AFTER MATCH SKIP TO NEXT ROW ]
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Mon_Jun_26_17_45_07_2023_724)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v2-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v2 5/7] Row pattern recognition patch (docs).
@ 2023-06-26 08:05 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-26 08:05 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 52 +++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 29 +++++++++++++--
 3 files changed, 148 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..e9bbd5bc7c 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,58 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ AFTER MATCH SKIP PAST LAST ROW
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..16478a3950 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,31 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses. <literal>AFTER MATCH SKIP PAST LAST
+    ROW</literal> or <literal>AFTER MATCH SKIP TO NEXT ROW</literal> controls
+    how to proceed to next row position after a match
+    found. With <literal>AFTER MATCH SKIP PAST LAST ROW</literal> (the
+    default) next row position is next to the last row of previous match. On
+    the other hand, with <literal>AFTER MATCH SKIP TO NEXT ROW</literal> next
+    row position is always next to the last row of previous
+    match. <literal>DEFINE</literal> defines definition variables along with a
+    boolean expression. <literal>PATTERN</literal> defines a sequence of rows
+    that satisfies certain conditions using variables defined
+    in <literal>DEFINE</literal> clause.
+
+<synopsis>
+[ AFTER MATCH SKIP PAST LAST ROW | AFTER MATCH SKIP TO NEXT ROW ]
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Mon_Jun_26_17_45_07_2023_724)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v2-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v2 5/7] Row pattern recognition patch (docs).
@ 2023-06-26 08:05 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-26 08:05 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 52 +++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 29 +++++++++++++--
 3 files changed, 148 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..e9bbd5bc7c 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,58 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ AFTER MATCH SKIP PAST LAST ROW
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..16478a3950 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,31 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses. <literal>AFTER MATCH SKIP PAST LAST
+    ROW</literal> or <literal>AFTER MATCH SKIP TO NEXT ROW</literal> controls
+    how to proceed to next row position after a match
+    found. With <literal>AFTER MATCH SKIP PAST LAST ROW</literal> (the
+    default) next row position is next to the last row of previous match. On
+    the other hand, with <literal>AFTER MATCH SKIP TO NEXT ROW</literal> next
+    row position is always next to the last row of previous
+    match. <literal>DEFINE</literal> defines definition variables along with a
+    boolean expression. <literal>PATTERN</literal> defines a sequence of rows
+    that satisfies certain conditions using variables defined
+    in <literal>DEFINE</literal> clause.
+
+<synopsis>
+[ AFTER MATCH SKIP PAST LAST ROW | AFTER MATCH SKIP TO NEXT ROW ]
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Mon_Jun_26_17_45_07_2023_724)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v2-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v2 5/7] Row pattern recognition patch (docs).
@ 2023-06-26 08:05 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-26 08:05 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 52 +++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 29 +++++++++++++--
 3 files changed, 148 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..e9bbd5bc7c 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,58 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ AFTER MATCH SKIP PAST LAST ROW
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..16478a3950 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,31 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses. <literal>AFTER MATCH SKIP PAST LAST
+    ROW</literal> or <literal>AFTER MATCH SKIP TO NEXT ROW</literal> controls
+    how to proceed to next row position after a match
+    found. With <literal>AFTER MATCH SKIP PAST LAST ROW</literal> (the
+    default) next row position is next to the last row of previous match. On
+    the other hand, with <literal>AFTER MATCH SKIP TO NEXT ROW</literal> next
+    row position is always next to the last row of previous
+    match. <literal>DEFINE</literal> defines definition variables along with a
+    boolean expression. <literal>PATTERN</literal> defines a sequence of rows
+    that satisfies certain conditions using variables defined
+    in <literal>DEFINE</literal> clause.
+
+<synopsis>
+[ AFTER MATCH SKIP PAST LAST ROW | AFTER MATCH SKIP TO NEXT ROW ]
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Mon_Jun_26_17_45_07_2023_724)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v2-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v2 5/7] Row pattern recognition patch (docs).
@ 2023-06-26 08:05 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-26 08:05 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 52 +++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 29 +++++++++++++--
 3 files changed, 148 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..e9bbd5bc7c 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,58 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ AFTER MATCH SKIP PAST LAST ROW
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..16478a3950 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,31 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses. <literal>AFTER MATCH SKIP PAST LAST
+    ROW</literal> or <literal>AFTER MATCH SKIP TO NEXT ROW</literal> controls
+    how to proceed to next row position after a match
+    found. With <literal>AFTER MATCH SKIP PAST LAST ROW</literal> (the
+    default) next row position is next to the last row of previous match. On
+    the other hand, with <literal>AFTER MATCH SKIP TO NEXT ROW</literal> next
+    row position is always next to the last row of previous
+    match. <literal>DEFINE</literal> defines definition variables along with a
+    boolean expression. <literal>PATTERN</literal> defines a sequence of rows
+    that satisfies certain conditions using variables defined
+    in <literal>DEFINE</literal> clause.
+
+<synopsis>
+[ AFTER MATCH SKIP PAST LAST ROW | AFTER MATCH SKIP TO NEXT ROW ]
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Mon_Jun_26_17_45_07_2023_724)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v2-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v2 5/7] Row pattern recognition patch (docs).
@ 2023-06-26 08:05 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-26 08:05 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 52 +++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 29 +++++++++++++--
 3 files changed, 148 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..e9bbd5bc7c 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,58 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ AFTER MATCH SKIP PAST LAST ROW
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..16478a3950 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,31 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses. <literal>AFTER MATCH SKIP PAST LAST
+    ROW</literal> or <literal>AFTER MATCH SKIP TO NEXT ROW</literal> controls
+    how to proceed to next row position after a match
+    found. With <literal>AFTER MATCH SKIP PAST LAST ROW</literal> (the
+    default) next row position is next to the last row of previous match. On
+    the other hand, with <literal>AFTER MATCH SKIP TO NEXT ROW</literal> next
+    row position is always next to the last row of previous
+    match. <literal>DEFINE</literal> defines definition variables along with a
+    boolean expression. <literal>PATTERN</literal> defines a sequence of rows
+    that satisfies certain conditions using variables defined
+    in <literal>DEFINE</literal> clause.
+
+<synopsis>
+[ AFTER MATCH SKIP PAST LAST ROW | AFTER MATCH SKIP TO NEXT ROW ]
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Mon_Jun_26_17_45_07_2023_724)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v2-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v2 5/7] Row pattern recognition patch (docs).
@ 2023-06-26 08:05 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-26 08:05 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 52 +++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 29 +++++++++++++--
 3 files changed, 148 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..e9bbd5bc7c 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,58 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ AFTER MATCH SKIP PAST LAST ROW
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..16478a3950 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,31 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses. <literal>AFTER MATCH SKIP PAST LAST
+    ROW</literal> or <literal>AFTER MATCH SKIP TO NEXT ROW</literal> controls
+    how to proceed to next row position after a match
+    found. With <literal>AFTER MATCH SKIP PAST LAST ROW</literal> (the
+    default) next row position is next to the last row of previous match. On
+    the other hand, with <literal>AFTER MATCH SKIP TO NEXT ROW</literal> next
+    row position is always next to the last row of previous
+    match. <literal>DEFINE</literal> defines definition variables along with a
+    boolean expression. <literal>PATTERN</literal> defines a sequence of rows
+    that satisfies certain conditions using variables defined
+    in <literal>DEFINE</literal> clause.
+
+<synopsis>
+[ AFTER MATCH SKIP PAST LAST ROW | AFTER MATCH SKIP TO NEXT ROW ]
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Mon_Jun_26_17_45_07_2023_724)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v2-0006-Row-pattern-recognition-patch-tests.patch"



^ permalink  raw  reply  [nested|flat] 26466+ messages in thread

* [PATCH v2 5/7] Row pattern recognition patch (docs).
@ 2023-06-26 08:05 Tatsuo Ishii <[email protected]>
  0 siblings, 0 replies; 26466+ messages in thread

From: Tatsuo Ishii @ 2023-06-26 08:05 UTC (permalink / raw)

---
 doc/src/sgml/advanced.sgml   | 52 +++++++++++++++++++++++++++
 doc/src/sgml/func.sgml       | 69 ++++++++++++++++++++++++++++++++++++
 doc/src/sgml/ref/select.sgml | 29 +++++++++++++--
 3 files changed, 148 insertions(+), 2 deletions(-)

diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 755c9f1485..e9bbd5bc7c 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -537,6 +537,58 @@ WHERE pos &lt; 3;
     <literal>rank</literal> less than 3.
    </para>
 
+   <para>
+    Window function <function>rpr</function> can be used with row pattern
+    common syntax to perform row pattern recognition in a query. Row pattern
+    common syntax includes two sub clauses. <literal>DEFINE</literal> defines
+    definition variables along with an expression. The expression must be a
+    logical expression, which means it must
+    return <literal>TRUE</literal>, <literal>FALSE</literal>
+    or <literal>NULL</literal>. Moreover if the expression comprises a column
+    reference, it must be the argument of <function>rpr</function>. An
+    example of <literal>DEFINE</literal> is as follows.
+
+<programlisting>
+DEFINE
+ LOWPRICE AS price &lt;= 100,
+ UP AS price &gt; PREV(price),
+ DOWN AS price &lt; PREV(price)
+</programlisting>
+
+    Note that <function>PREV</function> returns price column in the previous
+    row if it's called in a context of row pattern recognition. So in the
+    second line means the definition variable "UP" is <literal>TRUE</literal>
+    when price column in the current row is greater than the price column in
+    the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when
+    price column in the current row is lower than the price column in the
+    previous row.
+   </para>
+   <para>
+    Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be
+    used. <literal>PATTERN</literal> defines a sequence of rows that satisfies
+    certain conditions.  For example following <literal>PATTERN</literal>
+    defines that a row starts with the condition "LOWPRICE", then one or more
+    rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a
+    sequence of rows found, rpr returns the column at the starting row.
+    Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal>
+    and <literal>PATTERN</literal> clause is as follows.
+
+<programlisting>    
+SELECT company, tdate, price, rpr(price) OVER w FROM stock
+ WINDOW w AS (
+ PARTITION BY company
+ ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING
+ AFTER MATCH SKIP PAST LAST ROW
+ INITIAL
+ PATTERN (LOWPRICE UP+ DOWN+)
+ DEFINE
+  LOWPRICE AS price &lt;= 100,
+  UP AS price &gt; PREV(price),
+  DOWN AS price &lt; PREV(price)
+);
+</programlisting>
+   </para>
+
    <para>
     When a query involves multiple window functions, it is possible to write
     out each one with a separate <literal>OVER</literal> clause, but this is
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index 5a47ce4343..8069c58ca5 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable;
         returns <literal>NULL</literal> if there is no such row.
        </para></entry>
       </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>rpr</primary>
+        </indexterm>
+        <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Perform row pattern recognition using column specified
+        by <parameter>value</parameter> and returns the value of the column if
+        current row is the first matching row;
+        returns <literal>NULL</literal> otherwise.
+       </para></entry>
+      </row>
      </tbody>
     </tgroup>
    </table>
@@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable;
    Other frame specifications can be used to obtain other effects.
   </para>
 
+  <para>
+   Row pattern recognition navigation functions are listed in
+   <xref linkend="functions-rpr-navigation-table"/>.  These functions
+   can be used to describe DEFINE clause of Row pattern recognition.
+  </para>
+
+   <table id="functions-rpr-navigation-table">
+    <title>Row Pattern Navigation Functions</title>
+    <tgroup cols="1">
+     <thead>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        Function
+       </para>
+       <para>
+        Description
+       </para></entry>
+      </row>
+     </thead>
+
+     <tbody>
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>prev</primary>
+        </indexterm>
+        <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the previous row;
+        returns NULL if there is no previous row in the window frame.
+       </para></entry>
+      </row>
+
+      <row>
+       <entry role="func_table_entry"><para role="func_signature">
+        <indexterm>
+         <primary>next</primary>
+        </indexterm>
+        <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> )
+        <returnvalue>anyelement</returnvalue>
+       </para>
+       <para>
+        Returns the column value at the next row;
+        returns NULL if there is no next row in the window frame.
+       </para></entry>
+      </row>
+
+     </tbody>
+    </tgroup>
+   </table>
+
   <note>
    <para>
     The SQL standard defines a <literal>RESPECT NULLS</literal> or
diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml
index 0ee0cc7e64..16478a3950 100644
--- a/doc/src/sgml/ref/select.sgml
+++ b/doc/src/sgml/ref/select.sgml
@@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl
     The <replaceable class="parameter">frame_clause</replaceable> can be one of
 
 <synopsis>
-{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
-{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ]
+{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
+{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax]
 </synopsis>
 
     where <replaceable>frame_start</replaceable>
@@ -1074,6 +1074,31 @@ EXCLUDE NO OTHERS
     a given peer group will be in the frame or excluded from it.
    </para>
 
+   <para>
+    The
+    optional <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    defines the <firstterm>row pattern recognition condition</firstterm> for
+    this
+    window. <replaceable class="parameter">row_pattern_common_syntax</replaceable>
+    includes following subclauses. <literal>AFTER MATCH SKIP PAST LAST
+    ROW</literal> or <literal>AFTER MATCH SKIP TO NEXT ROW</literal> controls
+    how to proceed to next row position after a match
+    found. With <literal>AFTER MATCH SKIP PAST LAST ROW</literal> (the
+    default) next row position is next to the last row of previous match. On
+    the other hand, with <literal>AFTER MATCH SKIP TO NEXT ROW</literal> next
+    row position is always next to the last row of previous
+    match. <literal>DEFINE</literal> defines definition variables along with a
+    boolean expression. <literal>PATTERN</literal> defines a sequence of rows
+    that satisfies certain conditions using variables defined
+    in <literal>DEFINE</literal> clause.
+
+<synopsis>
+[ AFTER MATCH SKIP PAST LAST ROW | AFTER MATCH SKIP TO NEXT ROW ]
+PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...]
+DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...]
+</synopsis>    
+   </para>
+
    <para>
     The purpose of a <literal>WINDOW</literal> clause is to specify the
     behavior of <firstterm>window functions</firstterm> appearing in the query's
-- 
2.25.1


----Next_Part(Mon_Jun_26_17_45_07_2023_724)--
Content-Type: Text/X-Patch; charset=us-ascii
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
 filename="v2-0006-Row-pattern-recognition-patch-tests.patch"



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2016-05-08 01:53 Accurate list of Keywords / Datatypes? Robins Tharakan <[email protected]>
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2016-05-11 01:22   ` David G. Johnston <[email protected]>
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2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
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2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
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2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
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2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
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2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
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2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
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2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
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2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-26 08:05 [PATCH v2 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-26 08:05 [PATCH v2 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-26 08:05 [PATCH v2 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-26 08:05 [PATCH v2 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-26 08:05 [PATCH v2 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-26 08:05 [PATCH v2 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-26 08:05 [PATCH v2 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-26 08:05 [PATCH v2 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-26 08:05 [PATCH v2 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-26 08:05 [PATCH v2 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-26 08:05 [PATCH v2 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-26 08:05 [PATCH v2 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-26 08:05 [PATCH v2 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-26 08:05 [PATCH v2 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-26 08:05 [PATCH v2 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>
2023-06-26 08:05 [PATCH v2 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <[email protected]>

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